like :snoopy said...
4-2-1 tends to give midrange gains
4-1 tends to give top end gains



ceramic vs stainless.
there has been many many posts and arguments about this. But this is my take.

performance - SS tends to raise under hood temps but reduce actual engine temps due to it dissipating more heat through the metal and not just in the exhaust gasses.
Ceramic tends to reduce under hood temps but since it's not dissipating the extra heat, it tends to run the engine a little hotter.

appearance - ceramic vs polished, you decide. neither stays that way for long. And yes the BBQ paint trick works, but it dies after a while too.
(Especially with an OEM cat running 7500-8000RPM for almost an hour straight. The header glowed for a long time and there was not much left of the original coat or the BBQ paint. )

price - ceramic is always cheaper since they can hide blemishes and problems with the coating. But the problems may come back to haunt you later.

I went with a SS 4-2-1 because my engine runs hotter than most, I'm less concerned with underhood temps and IMO honda engines need all the midrange help they can get.